Multiple light valve lighting device or apparatus with wide color palette and improved contrast ratio

ABSTRACT

An apparatus is disclosed comprising a lamp which produces a first light which may be a white light; a first light valve, a second light valve, a first color separator, and a first aperture device. The first color separator receives the white light from the lamp, and separates the white light into a first color light and a first residual light. The first aperture device receives the first color light and the first aperture device can be controlled to modify a frequency of the first color light to the first light valve. The second light valve receives at least a portion of the first residual light. The first aperture device could also be controlled to substantially block at least a portion of the first color light.

FIELD OF THE INVENTION

[0001] The present invention relates to stage lighting devicesincorporating light valves for projecting images on a stage.

BACKGROUND OF THE INVENTION

[0002] Stage lighting devices incorporating light valves for theprojection of images are known in the art. Stage lighting devicesincorporating light valves are used to project patterns on a stage.Before electronic light valves, stage lighting devices used metalstencil patterns that were indexed on a wheel to produce the projectedpatterns upon the stage.

[0003] U.S. Pat. No. to 4,779,176 to Bornhorst titled “Light patterngenerator” describes glass substrates with aluminum coatings that areused as projection patterns in a lighting device. U.S. Pat. Ser. No.5,113,332 titled “Selectable mechanical and electronic patterngenerating aperture module” to Richardson describes an electronicaperture or light valve used to generate the patterns projected from alighting device. U.S. Pat. No. 5,758,956 titled “High intensity lightingprojectors” to Hutton describes a controllable image quality projectiongate providing advanced visual effects. Other types of electronic lightvalves have also been used with lighting devices. U.S. Pat. No.5,828,485 titled “Programmable light beam shape altering device usingprogrammable micromirrors” to Hewlett describes a digital micromirrordevice (“DMD”) that is used to alter the shape of light that isprojected onto a stage.

[0004] The prior art stage lighting devices are designed around a singlelight valve as the projection gate. The inventors have optimized theirinventions to work best as a lighting device. Many inventors prefer thesingle light valve system as it may have a reduced cost over multiplelight valve systems. High End Systems (Trademarked) of Austin, Tex. hasfound success with a multiple light valve projector in combination witha positioning mirror. The device called a Catalyst (Trademarked) is usedlike a periscope that mounts to the front of a video projector. Itallows static images or moving video to be projected anywhere within a3600 by 1800 hemisphere of movement. Images can be manipulatedlimitlessly in real-time from a dedicated control console. The preferredprojector type of the prior art is a three light valve system. Moreinformation can be found at:Http://www.highend.com/pdfbin/NewCatalyst.pdf. The device is limitedhowever as it uses a conventional multiple light valve projection systemand can only produce a limited color palette.

[0005] In the prior art a single light valve is used. An aperture devicecontaining filters or multiple aperture devices containing filters arelocated between a lamp producing white light and a single light valve tochange the color of the light from the lamp sent to the single lightvalve. The single light valve systems can not do full color imagesunless they spin an aperture device containing color filters of red,blue and green in front of the single light valve. The aperture devicecontaining the colors of red, blue and green is rotated, in the priorart, at a certain frequency in sync with the single light valve toproduce a full color image. Because each color is only on for a third ofthe time, much of the energy from the lamp is lost. An example of thistechnique is shown at http://howstuffworks.lycos.com/proiection-tv5.htm

[0006] With existing regular video projection, three light valves areused with the white light produced from a lamp separated into red, greenand blue as more of the light from the lamp is used to produce a fullcolor image

[0007] The problem is that for a video projection device built for videothe red, green and blue colors are specially selected.

SUMMARY OF THE INVENTION

[0008] The present invention discloses a lighting device using multiplelight valves which provide an improved contrast ratio from devices ofthe prior art. The lighting devices of embodiments of the presentinvention are capable of projecting a wide range of available colors.

[0009] The present invention allows a greater array of colors bothsaturated and less saturated to be used by first allowing the widestproduction of red, green and blue by a color separation system or deviceand then modifying the colors from the color separation system withaperture devices that contain color filters. Aperture devices modify theseparated colors.

[0010] It is one object of the present invention to construct a multiplelight valve lighting device with an improved lighting color palette.

[0011] It is yet another object of the present invention to construct amultiple light valve lighting device with an improved contrast ratio.

[0012] It is yet another object of the present invention to transmitcommands over a communication system to the multiple light valvelighting devices where custom color palettes may be selected remotely.

[0013] It is yet another object of the present invention for themultiple light valve device to automatically improve the contrast ratiobased upon the program material.

[0014] It is yet another object of the present invention for themultiple light valve lighting device to shutter the outputs of theindividual light valves upon a command over the communication system.

[0015] It is yet another object of the present invention for themultiple light valve lighting device to shutter all of the individuallight valves to produce a black out.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016]FIG. 1 shows a prior art multiple light valve projector opticalsystem comprised of three light valves;

[0017]FIG. 2 is a graph showing the light transmission versus wavelengthof the prior art system of FIG. 1;

[0018]FIG. 3 is a graph which compares the prior art FIG. 2 lighttransmission versus wavelength with the light transmission versuswavelength produced by the embodiment of FIG. 8 in accordance with thepresent invention;

[0019]FIG. 4A shows an aperture wheel for use with an embodiment of thepresent invention, such as FIG. 8, for modifying the bandwidths of red,blue or green light;

[0020]FIG. 4B shows a side view of the aperture wheel of FIG. 4A;

[0021]FIG. 5 is a graph representing three different slope conditions oflight transmission versus wavelength. The first set of slopescorresponds to the FIG. 8 embodiment and is also shown in FIG. 3. Theother two sets of slopes can also be obtained by the FIG. 8 embodimentby adjusting the aperture devices;

[0022]FIG. 6A shows an aperture wheel for use in the embodiment of FIG.8, with wedge shaped apertures;

[0023]FIG. 6B shows a side view of the aperture wheel of FIG. 6A;

[0024]FIG. 7 shows a remote console and a control system for a multiplelight valve lighting device in accordance with an embodiment of thepresent invention;

[0025]FIG. 8 shows an optical apparatus of an embodiment of the presentinvention using three light valves;

[0026]FIG. 9A shows an apparatus comprised of a shutter device or asingle color filter, a light blocking material, a motor shaft, and amotor which can be used in the embodiment of FIG. 8;

[0027]FIG. 9B shows a linear aperture device that can insert aperturesinto a light path which can be used in the embodiment of FIG. 8;

[0028]FIG. 10 shows two multiple light valve lighting devices connectedover a communication system to a remote console; and

[0029]FIG. 11 shows an apparatus which is basically the same as theapparatus of the embodiment of FIG. 8, except that electronicallyswitchable spectral filters have been substituted for aperture wheels(and their motors).

DETAILED DESCRIPTION OF THE DRAWINGS

[0030]FIG. 1 shows a prior art multiple light valve projector opticalsystem 100 comprised of light valves 150 g, 150 r and 150 b. Themultiple light valve projector optical system 100 is further comprisedof a lamp 110, a reflector 112, a polarization converter 118, a colorseparator 124 c, a color separator 124 y, reflector 130 a, a reflector130 d, a reflector 130 e, a color combining system 176, and a focusinglens 180.

[0031] The lamp 110 produces a white light whose path is illustrated byarrow 114. The white light or any light of a plurality of frequenciesmay be considered a first light of a plurality of frequencies within themeaning of various claims of the application. The lamp 110 has itsenergy focused by the reflector 112. The lamp 110 produces visible whitelight with the components of red, blue and green wavelengths. The lightfocused by the reflector 112 as shown by the arrow 114 is directed tothe polarization converter 118. The light exits the polarizationconverter 118 and is directed towards color separator 124 c as shown byan arrow 122. Color separator 124 c can be a dichroic color separationfilter that reflects red light in the direction of an arrow 132 whiletransmitting blue and green light in the direction of an arrow 160. Theaction by the color separator 124 c can be described as separating thewhite light into a first color light and a first residual light. Thefirst residual light may be comprised of one or more frequencies and a“portion” of the first residual light may be defined as including one ormore frequencies of the one or more frequencies of the first residuallight. Similarly a “portion” of any other particular light as referredto in this application, may be comprised of one or more frequencies ofthe one or more frequencies of that particular light.

[0032] The red light as shown by arrow 132 is directed towards thereflector 130 e. The reflector 130 e reflects the red light in thedirection of an arrow 134 towards the light valve 150 r. The blue andgreen light, or first residual light, transmitted by the color separator124 c is directed towards the color separator 124 y as shown by an arrow160. Color separator 124 y reflects blue light, which is directedtowards the light valve 150 b as shown by an arrow 164. Color separator124 y transmits green light towards reflector 130 a as shown by an arrow170. The action by the color separator 124 y can be described asseparating the first residual light into a second color light and asecond residual light. Reflector 130 a reflects the green light towardsthe reflector 130 d and the green light is reflected towards the lightvalve 150 g as shown by an arrow 174.

[0033] The red, green and blue lights that are received by the lightvalves 150 r, 150 g, and 150 b, respectively are next directed throughtheir corresponding light valve towards the color combining system 176.The red, green and blue lights are recombined to a common path and aredirected towards the focusing lens 180 as shown by an arrow 178. Thelens 180 forms an image from the lights which passes through the valves150 r, 150 b and 150 g and which are combined by combining system 176and directs the combined light in the direction of an arrow 182 to aprojection surface (not shown) where the image from the light valves 150r, 150 b, and 150 g is projected.

[0034]FIG. 2 is a graph showing slopes 250 of light transmission versuswavelength of the prior art system of FIG. 1. The slopes 250 show thetransmitted frequencies of light to be combined as the overall availablelight output at arrow 182. The lamp 110 provides white light, whichincludes light of a variety of wavelengths. As an example, about ninetypercent of a light component in the white light at arrow 114 having awavelength of 450 nanometers is transmitted through the lens 180 toarrow 182 (minus the normal losses associated with the various opticalcomponents), as shown by FIGS. 1 and 2. As another example, about zeropercent of a light component in the white light at arrow 114 having awavelength of 500 nanometers is transmitted through the lens 180 toarrow 182.

[0035] The prior art slopes 250 in FIG. 2 shows cutoff points 280 b, 270g, 260 g, and 240 r. FIG. 2 represents the transmission, and cutoff ofthe red, blue and green wavelengths created by the color separationfilters 124 c and 124 y of the prior art system 100 of FIG. 1. The bluelight created by the color separation filters 124 c and 124 y has acutoff point 280 b. A blue light cutoff 280 b in FIG. 2 is approximately472 nanometers (or abbreviated as nm).

[0036] Green light cutoffs are determined at two locations on the graph,270 g and 260 g. Green light cutoff 270 g is located at approximately518 nm and the green light cutoff 260 g is located at approximately 560nm. The red light cutoff 240 r is located on the graph at approximately615 nm.

[0037]FIG. 3 is a graph which compares the prior art FIG. 2 slopes 250of light transmission versus wavelength with the slopes 350 of lighttransmission versus wavelength produced by the embodiment of FIG. 8 inaccordance with the present invention. The slopes 350 show the availablefrequencies of light that can be transmitted from the lamp 810 to becombined and projected from the lens 880 in the direction of 882.

[0038] The present invention in the embodiment of FIG. 8 increases thebandwidth of the colors red, green and blue (shown by the dashed slopes350 of FIG. 3) versus the FIG. 2 prior art bandwidth of the colors red,green and blue (shown on the FIG. 3 graph by the solid slopes 250). Theprior art blue cutoff (approximately 472 nm) is shown at point 280 b onsolid line slope 250. The new blue cutoff is shown at a location on thedashed slope 350 identified by 382 b (approximately 478 nm).

[0039] The prior art green light cutoffs are shown at a location 270 g(approximately 518 nm) and a location 260 g (approximately 560 nm) onthe solid sloped line 250 in FIG. 3. The wider bandwidth of theembodiment of FIG. 8 is shown by locations 372 g (approximately 512 nm)and 362 g (approximately 566 nm) on the dashed sloped line 350 in FIG.3.

[0040] The prior art red light cutoffs are shown at a location 240 r(approximately 615 nm) on the solid sloped line 250 in FIG. 3. The widerbandwidth of the present invention is shown by a location 342 r(approximately 609 nm) on the dashed sloped line 350 in FIG. 3.

[0041] Generally speaking the greater bandwidth of the FIG. 8 embodimentversus the FIG. 1 prior art embodiment means that if the same amount oflight is supplied by lamp 110 and lamp 810, the system 800 of FIG. 8will produce more light at its output than the prior art system of FIG.1.

[0042]FIG. 4A shows an aperture wheel 400 for use with the embodiment ofFIG. 8 of the present invention for modifying the bandwidths of the red,blue or green light. The aperture wheel 400 is comprised of apertures410, 412, 414, 416, 418, 420, and 422, and motor 440.

[0043] The arrows 402 show that the wheel 400 can be rotated to bringthe apertures 412, 414, 416, 418, 420, and 422 in a desired position.The apertures 412, 414, 416, 418, 420, and 422 may be comprised ofbandwidth modifying filters and if desired at least one of the apertures412-422 may be left without a filter to pass light unobstructed. Any ofthe apertures 410-422 may also be aluminum or a suitable light blockingmaterial to act as a shutter. The motor 440 is used to rotate theaperture wheel 400. The aperture wheel 400 can be called an aperturedevice and can be used in the embodiment of FIG. 8 for any of theaperture devices in FIG. 8, such as aperture device 848 r.

[0044]FIG. 4B shows a side view of the aperture wheel 400 of FIG. 4A.Filters 412 a and 418 a are shown fixed over apertures 412 and 418,respectively, in any suitable way. The motor 440 is shown connected to amotor shaft 445. The motor shaft 445 is fixed to the aperture wheel 400in any suitable way.

[0045]FIG. 5 is a graph which includes three different available slopesof light transmission versus wavelength for the colors of red, green andblue light frequencies. Referring to FIG. 5, the three different cutoffsof 280 b, 382 b and 586 b are all blue cutoffs. The point 382 b isobtained by using color separators 824 c and 824 y specially selected tocombine to produce that slope cutoff point. In this case if we refer toFIG. 8, aperture devices 848 r and 844 r are most likely in a throughhole position so that no additional modification of the blue light fromthe color separators 824 c and 824 y takes place. If next we energize amotor to move a color modifying filter into place we can alter the colorof the blue light so that the frequency changes as shown by the slope280 b of FIG. 5. In this example, we are just altering the blue lightcolor and not the red or green. If we energize the motor on aperturedevice 848 r or 844 r to bring yet another different modifying filterinto place, we further alter the frequency of light being sent to theblue light valve 850 b of FIG. 8 so that the slope on the graph changesto 50% point 586 b of FIG. 5. At no time did the rest of the slopes forGreen and Red change as we were only changing the Blue aperture devices.

[0046] The 50% cutoff points for the blue, green, green, and red lighton the solid slopes 350 of FIG. 3 are at points 382 b, 372 g, 362 g, and342 r, respectively. The blue cutoff 382 b (approximately 478 nm) can bemodified by an aperture wheel like aperture wheel 400 of FIG. 4A oraperture wheel 600 of FIG. 6A in order to provide for selectablecutoffs. I.e. the aperture wheel 400 may be the aperture device 848 band/or the aperture device 844 b in the FIG. 8 embodiment. The motor ofthe aperture device 440 of FIG. 4a may rotate the apertures on theaperture device to place a color modifying filter in the light path ofthe blue light reflected by the color separator 824 y of FIG. 8

[0047] The green light cutoffs 372 g and 362 g can be modified by anaperture wheel like aperture wheel 400 of FIG. 4A or aperture wheel 600of FIG. 6A. The aperture wheel 400 or 600 may be the aperture device 848g or 844 g. The aperture wheel 848 g or 844 g may be controlled tomodify the cutoff of 372 g and 362 g to new selectable cutoffs of 270 g(approximately 512 nm) and 260 g (approximately 560 nm) on the slopesshown as dashed lines 250 or cutoffs of 576 g (approximately 525 nm) and566 g (approximately 552 nm) on the dashed slopes 550.

[0048] The red cutoff 342 r can be modified by an aperture wheel likeaperture wheel 400 of FIG. 4A or aperture wheel 600 of FIG. 6A as to nowprovide for selectable cutoffs. The aperture wheel 400 or 600 may be theaperture device 848 r or 844 r in FIG. 8. The aperture wheel 848 r or844 r may be controlled to modify the red light cutoff of 342 r(approximately 609 nm) to 240 r (approximately 615 nm) on the dashedslope 250 and 546 r (approximately 628 nm) on the dashed slopes 550 inFIG. 5.

[0049]FIG. 6A shows another type of aperture wheel 600. The aperturewheel 600 has trapezoidal apertures 612, 614, 616, 618, 620, and 622.The apertures 612-622 may be color filter sections such as dichroicfilters or other color filters known in the art. The apertures 612-622may also be aluminum or a light blocking material to act as a shutter.The apertures 612-622 are fixed to the central section 644 of theaperture wheel 600 by any suitable means. A motor 640 rotates theapertures 612-622 to a position in the path of a light. Shutters andcolor filters may be positioned in any aperture location (of apertures612-622) on the aperture wheel 600. The aperture wheel 600 may only useone or two apertures as desired and not all of the apertures 612-622need to have filters or light blocking material and some can be leftopen if desired. Blocking in the present application may mean blockingby shutter a particular color light without changing the frequency.

[0050]FIG. 6B shows a side view of the aperture wheel 600. A side viewof the apertures 618, 620, and 622 are also shown. Each of the apertures618, 620, and 622 may include a color filter or shutter. The motor 640has a motor shaft 645 that is fixed in any suitable manner to theaperture wheel 600 to rotate the aperture wheel 600. The aperture wheel600 can rotate with respect to the motor 640.

[0051]FIG. 7 shows a remote console 780, a power source 790, and acontrol system 760. The control system 760 would be part of and used ina lighting device such as lighting device 1050 of FIG. 10. The powersource 790 provides power to the lighting device, such as 1050 and theremote console 780 can control the lighting device 1050.

[0052] The control system 760 in FIG. 7 includes thermal monitoringdevice 714, sensor 716, sensor 718, a light valve driving device 720, amotor drive device 722, a lamp power supply 724, a power supply 726,microprocessor 728, and communications node 730.

[0053] The remote console 780 for generation of command signals receivespower from the power source 790 (which may be a power line) and thepower source 790 is coupled to the remote console 780 through conductors796 in a known manner. A communications cable 772 is connected betweenthe remote console 780 at connection point 770 and the control system760 at connection point 774. The communications used over thecommunication cable 772 may be serial data that contain unique addressesfor discrete communication with potentially a plurality of multiplelight valve lighting devices, such as for example, lighting device 1060or 1050 shown in FIG. 10. The communications used over the communicationcable 772 may be bi-directional or more than one communications systemmay be used for example that disclosed in my copending applicationtitled “METHOD AND APPARATUS FOR DIGITAL COMMUNICATIONS WITH LIGHTINGDEVICES” Ser. No. 09/394,300 filed Sep. 10, 1999, incorporated byreference herein.

[0054] Control system 760 of FIG. 7 may be enclosed within a housing ofa lighting device like that shown as 1050 of FIG. 10. The communicationsnode 730 of FIG. 7 receives command signals from the remote console 780over the communications cable 772 through the connection point 774 andthe conductors 734. The connection point 774 may be a suitable connectoras known in the art and is connected by conductors 734 to the node 730.The communications node 730 transfers data and commands from the remoteconsole 780 to microprocessor 728 through conductors 729.

[0055] The microprocessor 728 may also include the memory necessary forthe operating system and the processing of commands. The microprocessor728 may be comprised of several microprocessors or it may be constructedof several discrete logic circuits. Power supply 726 is connectedthrough conductors 736 and power connection point 794 to the powersource 790. The power source 790 provides the necessary power to thepower supply 726 through connection point 794 and through internalconductors 736 and to the lamp power supply 724 through conductors 725.The power supply 726 is connected to the microprocessor 728 throughconductors 727 and to the lamp power supply 724 through conductors 725.The lamp power supply 724 is connected to the lamp 710 throughconductors 711. The lamp power supply 724 may also receive controlsignals through the conductor 732 from the microprocessor 728.

[0056] The microprocessor 728 receives thermal information from thethermal monitoring device 714 via conductors 719. The thermal monitoringdevice 714 may receive information from multiple thermal sensors such asthe sensors 718 and 716 through conductors 717 and 715, respectively.The sensors 718 and 716 can be any thermal sensor as known in the art.

[0057] The microprocessor 728 connects to the motor drive device 722through conductors 723 and may provide power and control signals to themotors 846 r, 840 r, 846 g, 840 g, 846 b, and 840 b. The motor drivedevice 722 connects to the motors 846 r, 840 r, 846 g, 840 g, 846 b and840 b through conductors 747 r, 741 r, 747 g, 741 g, 747 b and 741 b,respectively. The motors 846 r, 840 r, 846 g, 840 g, 846 b and 840 brotate aperture wheels 848 r, 844 r, 848 g, 844 g, 848 b and 844 b,respectively. The microprocessor 728 is connected to the light valvedriving device 720 through conductors 721. The light valve drivingdevice 720 controls the light valves 850 r, 850 g and 850 b overconductors 752 r, 752 g, and 752 b. The conductors 736, 734, 729,727,723,725,711,721,752 r, 752 g, 752 b, 747 r, 741 r, 747 g, 741 g, 747b, 741 b, 732, 717, 715, and 719 are shown simplified. The conductorsmay be multiple conductors and may be wired or copper conductors such asfor example a circuit board as known in the art.

[0058]FIG. 8 shows an optical apparatus 800 of an embodiment of thepresent invention of the invention using three light valves 850 g, 850b, and 850 r. The apparatus 800 also includes a lamp 810, polarizationconverter 818, reflectors 812, 830 a, 830 d, 830 e, color separators 824c and 824 y, motors 840 r and 846 r and aperture wheels 844 r and 848 r,motors 840 b and 846 b and aperture wheels 844 b and 848 b, motors 840 gand 846 g, and aperture wheels 844 g and 848 g, a color combining device876, and a focusing lens 880.

[0059] The lamp 810 has its energy focused by the reflector 812. Thelamp produces visible white light with light components having red, blueand green wavelengths. The white light focused by the reflector 812 asshown by an arrow 814 is directed to the polarization converter 818. Thewhite light exits the polarization converter 818. The purpose of apolarization converter is known in the art. It converts the unpolarizedwhite light from the lamp 810 and reflector 812 into polarized light.The light valves 850 g, 850 b, and 850 r operate with polarized light.In one controlled condition the light valves 850 g, 850 b, and 850 r letpolarized light pass through and in the other controlled condition lightis blocked from passing. Color separator 824 c can be a dichroic colorseparation filter that reflects or separates out red light in thedirection of an arrow 828 while transmitting or separating out aresidual light comprised of blue and green light in the direction of anarrow 860. The color red light which is reflected at the first colorseparator 824 c can be called the first color light in a process inaccordance with an embodiment of the present invention.

[0060] The red light as shown by arrow 828 is directed towards the twoaperture wheels 848 r (driven by the motor 846 r) and 844 r (driven bythe motor 840 r). The aperture wheels 848 r and 844 r may be similar toaperture wheels shown in FIGS. 4A-B and 6A-B and may be consideredaperture devices by themselves or in combination or in combination withthe motors 840 r and 848 r. The red light may pass through the selectedfilters or shutters positioned by the aperture wheels 848 r and 844 r inthe path of the red light at the location shown by arrow 828 and maynext travel in the direction of an arrow 832 to the reflector 830 e. Thered color light next travels in the direction of an arrow 834 towards avariable aperture 892 r. The variable aperture 892 r may be an iris. Theterm iris, generally speaking, is known in the art. The variableaperture 892 r may be motorized. The variable aperture 892 r may act asa mask to change a rectangular image created by a rectangular lightvalve, which is the type of light valve that light valve 850 r may be,to a round image that is adjustable. The red light passes through thevariable aperture 892 r, then through the light valve 850 r where thered light is controlled through the light valve 850 b in a manner knownin the art. The red light may pass though the light valve 850 b to thecolor combining device 876.

[0061] The residual blue and green light transmitted or separated out bycolor separator 824 c is directed towards the color separator 824 y asshown by arrow 860. Color separator 824 y reflects blue light, which isdirected towards the two aperture wheels 848 b (driven by the motor 846b) and the aperture wheel 844 b (driven by the motor 840 b). Theaperture wheels 848 b and 844 b may be similar to those shown in FIGS.4A-B or 6A-B and may be thought of separately or in combination or incombination with the motors 840 b and 846 b as aperture devices. Theblue light may pass through a selected filter or shutters (similar tothat shown in FIGS. 4A-B or 6A-B) positioned by the aperture wheels 848b and 844 b in the path of the blue light at the location of arrow 862and may next travel in the direction of arrow 864 towards a variableaperture 892 b. The variable aperture 892 b may be an iris. The variableaperture 892 b may be motorized. The variable aperture 892 b may act asa mask to change a rectangular image created by a rectangular lightvalve, which is the type of light valve that light valve 850 b may be,to a round image that is adjustable. The blue light passes through thevariable aperture 892 b, then through the light valve 850 b where theblue light is controlled through the light valve 850 b in a manner knownin the art. The blue light may pass though the light valve 850 b to thecolor combining device 876.

[0062] Color separator 124 y transmits or separates out green lighttowards reflector 830 a as shown by an arrow 870. Reflector 830 areflects the green light towards the two aperture wheels 848 g (drivenby the motor 846 g) and the aperture wheel 844 g (driven by the motor840 g). Aperture wheels 848 g and 844 g may be similar to those shown inFIGS. 4A-B or FIGS. 6A-B and may be considered to be separately or incombination, or in combination with motors 846 g and 840 g to beaperture devices. The blue light may pass through a selected filter orshutter positioned by the aperture wheels 848 g or 844 g in the lightpath and may next travel in the direction towards the reflector 830 d.

[0063] The green light is reflected off of reflector 830 d in thedirection of the arrow 874 towards a variable aperture 892 g. Thevariable aperture 892 g may each be an iris. The variable aperture 892 gmay be motorized. The variable aperture 892 g may act as a mask tochange a rectangular image created by a rectangular light valve, whichis the type of light valve that light valve 850 g may be, to a roundimage that is adjustable. The green light passes through the variableaperture 892 g, then through the light valve 850 g where the green lightis controlled through the light valve 850 g in a manner known in theart. The green light may pass though the light valve 850 g to the colorcombining device 876.

[0064] The color combining device 876 combines the red, green and bluelight controlled by the light valves 850 g, 850 b, and 850 r and thecombined light is sent in the direction of the arrow 878 towards a prism890 which may be a Dove prism as known in the art for rotation of imagescreated by the light valves 850 g, 850 b, and 850 r. The prism 890 maybe rotated with a motor as known in the art. The green light may passthrough the prism 890 and then to the focusing lens 880. An image isfocused in the direction of arrow 882 onto a projection surface notshown.

[0065]FIG. 9A shows an apparatus 900 comprised of a shutter device,single color filter, or light blocking material 902, a motor shaft 904,and a motor 906. The single color filter 902 can be rotated into a lightpath by the motor 906. The filter 902 rotates with respect to the motor906 on the shaft 904. The shaft 904 is rotatably connected to the motor906, and the shaft 904 is fixed to the filter or light blocking material(shutter) 902 in any suitable way. Arrows 912 show the direction of thefilter or light blocking material 902 when the motor 906 is energizedand the shaft 904 is rotated. Apparatus 900 can be considered anaperture device in accordance with the present invention and can beplaced in the FIG. 8 embodiment in the same locations as any of theaperture devices for example 844 r or 846 r of FIG. 8. Or 846 r could bean aperture device that is an aperture wheel while 844 r could beapparatus 900 of FIG. 9 and might act as a shutter only as 902 is fittedwith light blocking material.

[0066]FIG. 9B shows a linear aperture device 950 that can insertapertures into a light path. The linear aperture device 950 is comprisedof apertures 930 and 932, a mounting plate 938, a power nut 940, a wormgear shaft 942, and a motor 944. The apertures 930 and 932 may containcolor filters or light blocking materials. The apertures 930 and 932 arefixed to the mounting plate 938 that is in turn fixed to the power nut940. The power nut 940 is driven by a worm gear shaft 942 by the motor944. The worm gear shaft 942 is rotatably connected to the motor 944.Arrows 946 show the direction of movement of the apertures 930 and 932when the motor worm gear shaft 942 is rotated. The device 950 of FIG. 9Bcan be used in any location where an aperture device is used. Forexample it could be place in the location of 844 r of FIG. 8. It couldplace a color filter or a light blocking material into the path of thered light before the light passes through to the reflector 830 e.

[0067] Video projection systems used for projecting conventional videoin the prior art have a preferred color range for video. For example inthe prior art devices, such as FIG. 1, the color separators 124 c and124 y work together as known in the art to separate white light emittedfrom a lamp into separate red, green and blue components. Specificationsof the color separators 124 c and 124 y are designed so that thebandwidths of red, green and blue light are controlled to produce thebest video image. This is important to video because if the colors ofred, blue and green light have too wide a bandwidth, the video imagescan appear washed out and unnatural looking to the viewer. If thebandwidths of red, green, and blue light are too narrow the color willlook very saturated but the projector can suffer from poor overalloutput. An example of the prior art bandwidths and cutoff frequenciesfor video is shown in FIG. 2.

[0068] The present invention in various embodiments specifies a colorseparation system with wide bandwidths and a selectable bandwidth systemfor modifying the color palette of a multiple light valve lightingdevice for lighting applications. FIG. 3 shows the prior art cutoffs forred, green and blue light on the solid slope line 250 on thetransmission graph. The dashed line 350 shows an increased bandwidth ofthe present invention over the prior art for red, green and blue light.It is preferred to have the greatest bandwidth possible for each of thered, green and blue colored lights. Once the wide bandwidth colorseparation system of the present invention is used, selectable aperturewheels or aperture devices with variable cutoff frequencies can beplaced in the locations of for example aperture wheels 848 g, 844 g, 848b, 844 b, 848 r and 844 r of FIG. 8 to provide adjustable bandwidths forthe red, green and blue wavelengths.

[0069]FIG. 5 illustrates a wide bandwidth color separation system of thepresent invention of red, green and blue light as shown by the solidslopes 350. Selectable aperture wheels, such as apertures wheels 400 and600 of FIG. 4A-B and FIG. 6A-B, respectively, can be used as such as oneor more of aperture wheels 848 r and 844 r (to modify the red light) asone or more of aperture wheels 848 b and 844 b (to modify the bluelight) and as one or more of aperture wheels 848 g and 844 g (to modifythe green light). As in FIG. 8, the aperture wheels 848 r and 844 r, 848b and 844 b, 848 g and 844 g can be used before the light valves (suchas 850 r, 850 b, and 850 g in FIG. 8, respectively) and after the one ormore color separators (such as 824 c and 824 y). In the preferredversion of the present invention, the selectable aperture wheels oraperture devices are located before the light valves (such as aperturewheels 848 r and 844 r before light valve 850 r) but it is possible tolocate the selectable aperture wheels after the light valves.

[0070] The solid slopes 350 in FIG. 5 shows the FIG. 8 embodiment withthe aperture devices 848 r, 848 g, 848 b, and 844 r, 844 g, and 844 b inan unmodified case, i.e. all of the aperture devices act as throughholes with no filter. In FIG. 5 the unmodified color separation cutoffpoint of the blue light is shown as 382 b on the solid slopes 350 andhas a cutoff of approximately 478 nm. In the “unmodified case” theaperture wheel 444 like that shown in FIG. 4A or aperture wheel 600 ofFIG. 6A has an aperture (such as one of apertures 410-422 or apertures612-622) selected into the blue light path that is a through hole withno filter. In this way the blue light reflected from color separator 824y of FIG. 8 passes freely through the selected apertures of the aperturewheels 848 b and 844 b without modifying the cutoff of the blue light.The green light and the red light are treated similarly to the bluelight in the unmodified case.

[0071] The dashed slopes 250 shows a case where one of the aperturewheels for each colored light path has been rotated so that an aperturewith the appropriate cutoff filter has been placed into the appropriatelight path. For example, 280 b shows a modified cutoff over 382 b. The280 b cutoff is approximately 472 nm and it is now apparent that thebandwidth has been reduced. The 280 b cutoff was produced when one ofthe aperture wheels 848 b or 844 b of FIG. 8 was rotated so that anaperture with the appropriate cutoff filter was placed into the bluelight path.

[0072] The term cutoff filter, as used in this application, is a filterdesigned to cutoff unwanted frequencies and to produce a desiredfrequency range. An aperture device or component of an aperture devicecomprised of a group of cutoff filter would allow for the selection ofdifferent cutoff frequencies. The selection of different frequencieswould appear visually as modifications of the original colors of light.When a frequency is modified from an original frequency different cutofffilters representing different cutoff frequencies are selected to beplaced in the path of light after a color separator.

[0073] The dashed slopes 550 shows a case where one of the aperturewheels for each colored light path has been rotated so that an aperturewith a different cutoff filter has been placed into the appropriatelight path. For example, by rotating one of the aperture wheels 848 b or844 b to a new aperture, a different cutoff filter can be placed intothe blue light path producing a result like that of 586 b of FIG. 5.When the aperture wheel, such as wheel 848 b is rotated to place acutoff filter that produces the results of 586 b of FIG. 5 into place,it is clear that the bandwidth of the blue light has been substantiallynarrowed over that of the unmodified bandwidth having a cutoff point at382 b. The cutoff point of 586 b is approximately 460 nm.

[0074] It could be possible to just simply electronically switch off(preventing the light to pass through the light valve) all of the areasaround a round transmitted image created by the light valves 850 g, 850b, and 850 r in FIG. 8, by the light valves themselves. However it canbe possible to see a ghost image of the areas surrounding the roundimage created by the light valves 850 g, 850 b, and 850 r because eachof the light valves may not be capable of switching off one hundredpercent (100%) of the light surrounding the round image. With a variableaperture, (such as variable apertures 892 r, 892 g, and 892 b) the areasaround the desired round image can be masked.

[0075] The irises or variable apertures 892 r, 892 g, and 892 b for thecorresponding individual light valves 850 r, 850 g, and 850 b,respectively, may be driven by motors as known in the art and mayrespond individually or all together. The size of the aperture createdby each of the variable apertures 892 r, 892 g, and 892 b can becontrolled by commands sent from the remote console 780 in FIG. 7 ifdesired.

[0076] It is also possible to have aperture wheels that containdifferent types of apertures located in the variable aperture positionof 892 r, 892 b and 892 b. Aperture wheels that contain different typesof apertures are known in the art as gobo wheels. They are also drivenby motors. The gobo wheels containing two or more apertures each, mayrespond individually to modify the aperture size prior to thecorresponding appropriate light valve, such as 850 r, 850 g, or 850 b orgobo wheels may respond all together to modify the aperture prior to allthe light valves 850 r, 850 g, or 850 b.

[0077] Variable apertures, such as variable apertures 892 g, 892 b, and892 r can be used as in FIG. 8 before corresponding light valves 850 g,850 b, and 850 r, respectively. In either case the light valves 850 g,850 b, and 850 r can be a reflective or a transmissive type. Variableapertures, such as variable apertures 892 g, 892 b, and 892 r can alsobe used after corresponding light valves 850 g, 850 b, and 850 r,respectively, but before the color combining device 876. In either casethe variable apertures 892 g, 892 b, and 892 r should also be used afterwhite light has been separated into the component colors of light, whichin this case is green, blue, and red light.

[0078] While only two bandwidth modification examples are shown in FIG.5 for the modification from the unmodified slope 350 of FIG. 5, it isclear that many more incremental modifications can take place for eachof the blue, green and red lights. An aperture wheel, such as aperturewheel 848 b, 848 g, 848 r, 844 b, 844 g, or 844 r or aperture device maycontain many more filters for further modifying the bandwidth.

[0079] In FIG. 5, the green light spectrum from the color separationsystem of an embodiment of the present invention is shown on the solidsloped line 350 which includes the green cutoff points 372 g and 362 g.The solid sloped line 350 is again the unmodified case for FIG. 8, i.e.a through hole for all of the aperture devices or aperture wheels. Theaperture wheels 848 g and 844 g for green light are positioned in frontof the green light valve 850 g in FIG. 8 similar to the way the aperturewheels 848 b and 844 b are positioned for the blue light valve 850 bdiscussed above. The green light transmitted through color separator 824y of FIG. 8 reflects off of reflector 830 a and passes through theaperture wheels 848 g and 844 g. The aperture wheels 848 g and 844 g maybe similar to aperture wheel 400 of FIG. 4A or aperture wheel 600 ofFIG. 6A.

[0080] If one of the aperture wheels of 848 g and 844 g is rotated toposition a cutoff filter into the green light path at the location ofarrow 872 in FIG. 8, a modification to the green light color cutoff cantake place. For example, cutoff points 270 g and 260 g are shown ondashed slopes 250 of FIG. 5 and together show a narrower band of greenlight than cutoff points 372 g and 362 g for the unmodified case. Theresult of narrowing the green bandwidth to the bandwidth between thecutoff points of 270 g and 260 g was accomplished by rotating a cutofffilter into the green light path at location of arrow 872 in FIG. 8 byone of the aperture wheels 848 g or 844 g of FIG. 8. If yet a differentcutoff filter were to be placed into the green light path by one of theaperture wheels 848 g or 844 g of FIG. 8 then we can see the results onthe dashed slopes 550 on which the cutoff points 576 g and 566 g arelocated in FIG. 5. The cutoff points of 576 g and 566 g of FIG. 5 haveproduced a substantially narrower bandwidth and in turn a more saturatedgreen color than the original unmodified bandwidths on the solid slope350 corresponding to the cutoff points of 372 g and 362 g.

[0081] It is important to note that it is possible to use combinationsof cutoff filters to modify the color of light produced by the colorseparation system of the present invention. For example, in FIG. 5 wecould select a cutoff filter to be placed on the aperture wheels (suchas one of aperture wheels 848 g or 844 g) that only modifies one side ofthe green bandpass. In this example we might only modify the originalcutoff point 372 g to a cutoff point of that shown by 576 g yet therewill be no modification to the cutoff point of 362 g of the green light.Combinations of high pass cutoff and low pass cutoff filters can allowfor many variations in the green color bandwidth.

[0082] Cutoff point 342 r of FIG. 5 shows an unmodified color separationcutoff for the red light on the unmodified solid slopes 350. In theunmodified state the aperture wheels 848 r and 844 r of FIG. 8 have beenrotated to an unfiltered aperture for the cutoff point of 342 r. Amodification to the cutoff point of 240 r of dashed line slopes 250, isproduced when an aperture containing a cutoff filter is rotated intoposition by one of the aperture wheels 848 r or 844 r of FIG. 8. Forexample, the cutoff point of 240 r on the dashed slopes 250 produces anarrower bandwidth red than the cutoff point of 342 r. Additional cutofffilters can be rotated into place by the aperture wheels 848 r or 844 rof FIG. 8 to produce a cutoff point like 546 r of FIG. 5 on the dashedslopes 550.

[0083] Lighting devices are often used on a stage where total darknessis possible. It is desirable to have high contrast ratios on theprojection surface (such as surface on which the combined light isprojected towards in the direction shown by arrow 882 in FIG. 8) betweenthe image to be projected and the part of the projection surface that issupposed to be absent of any light. For instance, a multiple light valvelighting device might normally produce a rectangular image. This isbecause many of the available light valves have a rectangular apertureas known in the art. It could be a requirement for the lighting deviceto project a round image. While projecting the round image it is mostdesirable to effectively black out the outside corners of therectangular image surrounding the round image. Unfortunately, lightvalves are not 100% effective in blocking out all the light when in thelight blocking state. This means that an audience might still see aghost of the original rectangular image when the lighting device isprojecting the round image. In order to improve this situation undercertain conditions, the invention uses apertures with light blockingmaterial (or shutters) on the aperture wheels to block the light beforeit passes through the light valve. For example, if a round image werecomprised entirely of blue and red light and as there is no need for thegreen light, a shutter would be placed into the path of the green lightbefore the green light passes through the green light valve. In theembodiment of the present invention of FIG. 8, aperture wheel 848 g or844 g may contain at least one shutter aperture for blocking the path oflight. In the prior art when projecting images were comprised of red andblue light only, some small amount of green light would leak through thegreen light valve and further reduce the contrast ratio. With theembodiment of the present invention of FIG. 8, when an image isprojected and is comprised entirely of red and blue light, an aperturecontaining a shutter would be placed, (such as on aperture wheel 848 gor 844 g) to block the green light from passing through the aperturewheel (such as aperture wheel 848 g or 844 g) to the green light valve(such as valve 850 g).

[0084] Similarly, when an image is projected entirely of green and bluelight an aperture containing a shutter would be placed (such as onaperture wheel 848 r or 844 r) to block the red light from passingthought the aperture wheel to the red light valve (such as 850 r). Alsosimilarly when an image is projected entirely of green and red light anaperture containing a shutter would be placed (such as on aperture wheel848 b and 844 b) to block the blue light from passing through theaperture wheel to the blue light valve (such as valve 850 b). Dependingon what the image is comprised of, more than one aperture devices mayblock the light to more than one light valves. For instance, if theimage is comprised of only blue light then it is possible to block thelight to the red and green light valves.

[0085] When the lighting device, such as lighting device 1050 of FIG. 10of the present invention, is not being used to project an image, such asvia light shown by dashed lines 1055 and 1054, the aperture wheels (848r and 844 r, 848 g and 844 g, 848 b and 844 b) for the red, green andblue light can rotate to place shutters to block the red, green and bluelight from passing through to their prospective light valves (such as850 r, 850 g, and 850 b). In this way the invention prevents any lightleakage from passing through the red, green and blue light valvesinsuring a good black out in very dark conditions.

[0086]FIG. 4A shows an aperture wheel 400 with round apertures 410-422.The apertures 410-422 would be sized to allow the desired amount oflight to pass through each aperture and then to the appropriate lightvalve. The apertures 410-422 on the aperture wheel 400 of FIG. 4A couldalso be of different shapes including rectangular or square. Any of theapertures 410-422 may have cutoff filters or color modifying filters,contain no filter and be a through hole, or may contain a shutter.

[0087]FIG. 6A shows an aperture wheel 600 with wedge shaped apertures612-622. The apertures 612-622 would be sized to allow the light passingthrough the appropriate aperture on it's way to the appropriate lightvalve so that all the desired light would pass through the light valve.Any of the apertures 612-622 may have cutoff filters or color modifyingfilters, contain no filter and be a through hole, or may contain ashutter.

[0088] It is possible that the aperture wheels 848 r, 848 b and 848 gmay only be used as shutters and contain no cutoff filters. In this caseonly a single shutter aperture may be needed. This could improve thespeed of the shutter allowing faster transitions between passing andblocking the light to the appropriate light valve (such as one of lightvalves 850 g, 850 b, and 850 r). FIG. 9A shows single aperture device900 that could either contain a filter or a shutter.

[0089] Various aperture devices can be used to place apertures into andout of a light path instead of an aperture wheel. FIG. 9B shows anaperture slide device 950 where apertures 930 and 932 are moved linearlyinto and out of the light path. Either aperture 930 or aperture 932 cancontain filters of light blocking material. The aperture slide device950 can be used instead of or combined with one or more of the aperturewheels 848 r, 848 g, 848 b, 844 r, 844 g, or 844 b, and at any of thelocations of those aperture wheels in the FIG. 8 embodiment.

[0090] Instead of a mechanical aperture device that places filters intoa light path, an aperture device like an electronically switchablespectral filter like that produced by ColorLink of Boulder Colorado(www.colorlink.com) could be used for modification of the color producedby the color separation system. By chromatically manipulatingpolarization, the switchable spectral filter can be designed to provideseveral different cutoff frequencies used to modify the color spectrumsent by a color separator to a light valve (such as light valves 850 g,850 r, and 850 b of FIG. 8).

[0091]FIG. 11 shows the apparatus 1100 which is basically the same asthe apparatus 800 of the embodiment of FIG. 8, except thatelectronically switchable spectral filters have been substituted foraperture wheels (and their motors). Electronically switchable filters111 Or and 1115 r have been substituted for aperture wheels 848 r and844 r (and their motors), electronically switchable filters 1110 b and1115 b have been substituted for aperture wheels 848 b and 844 b (andtheir motors), and electronically switchable filters 1110 g and 1115 ghave been substituted for aperture wheels 848 g and 844 g (and theirmotors).

[0092]FIG. 7 shows a control system 760 for controlling aperture wheels848 r, 844 r, 848 g, 844 g, 848 b, and 844 b and lighting valves 850 r,850 g, and 850 b of the FIG. 8 embodiment. The control system 760 andthe remote control 780 is used for the operation of a multiple lightvalve lighting device such as device 1050 of FIG. 10.

[0093] In operation, signals are sent over a communications system fromthe remote console 780 to the control system 760 through the wiringconductors 772. The communication system may be used to send programmaterial to the control system 760 from the remote console 780. Theprogram material may provide information as to how the light valves 850r, 850 g, and 850 b are controlled to produce an image. Some examples ofprogram material are computer graphic and video signals. It is alsopossible that a second communication system between the remote console780 and the control system 760 may be used to send live video orgraphical information to be stored into memory of the microprocessor 728of FIG. 7.

[0094] The control system 760 has a communications node 730 forreceiving communication signals from the remote console 780. Thecommunications node 730 passes the signals to the microprocessor 728through the conductors 729. The microprocessor 728 receives the data asreceived by the communication node 730 and first determines if theunique address data contained from the received data is the correctaddress as known in the art. If the microprocessor 728 determines thatit has received a correct address contained within the received data,the microprocessor 728 may next act upon a command signal containedwithin the received data that is sent from the remote console 780 overthe communications system. If a command signal is sent from the remoteconsole 780 that contains a command for modification of the green color,the microprocessor 728 sends control signals via conductors 723 to themotor drive device 722 that in turn sends the appropriate controlsignals to the motors 840 g or 846 g.

[0095] The microprocessor 728 may also receive commands from the remoteconsole 780 to control the light valves 850 r, 850 g, and 850 b. Themicroprocessor 728 sends control signals via the conductors 721 to thelight valve controlling device 720. The light valve controlling device720 determines which one of the light valves of light valves 850 r, 850g, and 850 b, the microprocessor 728 desires to control, and sends theappropriate control signals to the light valves 850 r, 850 g or 850 bthough conductors 752 r, 752 g, or 752 b, respectively.

[0096] The microprocessor 728 receives its necessary operating powerfrom the power supply 726 through conductors 727 and also routes powerthrough conductors 729, 721, 719 and 723 to the communications node 730,the light valve controlling device 720, thermal monitoring device 714,and the motor drive device 722. The power supply 726 also supplies powerto the lamp power supply 724 via conductors 725. The lamp power supply724 may receive control signals from the microprocessor 728 throughconductors 732. The lamp power supply 724 supplies the necessary powerto operate the lamp 710. The lamp power supply 724 may be variable so asto supply variable power to the lamp 710.

[0097] The lamp power supply 724 may be capable of supplying power tothe lamp 710 in excess of the manufacturer's continuous rated powerlevel, for example if the lamp 710 is rated by the manufacturer at 200watts the power supply 724 may deliver upon signals 300 (three hundred)watts or greater to the lamp 710. It is possible to control the amountof power to the lamp 710 in accordance with the amount of light energyto pass through a particular light valve (such as one of light valves850 r, 850 g, or 850 b). For example more saturated colors have lessenergy to pass through a light valve while less saturated colors passmore energy through the light valves. If one or more of the lightvalves, such as light valves 850 r, 850 g, and 850 b has a limit as tohow much energy can be transmitted through the light valve the power tothe lamp 810 may need to be regulated to reduce the energy. If one ormore of the light valves 850 r, 850 g, or 850 b has a limit as to howmuch energy can be blocked by that light valve, the power to the lamp810 may have to be regulated to reduce the energy. It can be possibleusing duty cycle control to increase the power to the lamp 810 for briefdurations so that light energy passing through the light valves 850 r,850 g, and 850 b is of higher energy than normally would be allowed as acontinuous duty. By varying the power to the lamp 810 under differentconditions, the lighting device 1050 of FIG. 10 can be optimized formaximum light output under a variety of conditions. In FIG. 7, thecontrol system 760 may automatically adjust the power to the lamp 810 bydetermining the color spectrum in use, the placement of an aperturedevice, such as an aperture on one of aperture wheels 848 r, 844 r, 848g, 844 g, 848 b, or 844 b into the light path, the control condition ofa light valve (such as one of light valves 850 r, 850 g, or 850 b), oreven the physical placement of the lighting device 1050 of FIG. 10.

[0098] It is also possible for the lighting device 1050 of FIG. 10, toautomatically close and open light blocking apertures (shutters), suchas on aperture wheel 848 r, based upon the state of the light valves(such as light valve 850 r) as controlled by the light valve controllingdevice 720 as determined by the microprocessor 728 of FIG. 7. Forexample, when the green light valve 850 g of FIG. 7 of an embodiment ofthe present invention is controlled to the light blocking state for anygiven amount of time the green aperture device 844 g can block the lightpath of the green light from reaching the green light valve 850 g. Themicroprocessor 728 of FIG. 7 monitors the state of the red, green andblue light valves 850 r, 850 g, and 850 b, respectively, as controlledby the light valve controlling system 720 and if any of the light valvesare determined to be in the light blocking state for any given period oftime, the microprocessor 720 will next send control signals to the motordrive device 722 of FIG. 7 to operate one of the motors 846 r, 840 r,846 g, 840 g, 846 b or 840 b of the respective light valves to rotatethe motor and change the aperture of the aperture device such as one ofaperture wheels 848 r, 844 r, 848 g, 840 g, 848 b or 844 b. The lightblocking state is defined as when a light valve of light valves 850 r,850 g, and 850 b are controlled by the light valve controlling device720 to substantially block the light from passing through the lightvalve onward to the projection lens.

[0099] If the microprocessor 728 determines that all three light valves850 r, 850 g, and 850 b are in the light blocking state, all of theaperture devices, such as aperture devices 848 r, 844 r, 848 g, 844 g,848 b, and 844 b may block the light going to their respective lightvalves. This may be done automatically by monitoring the status of thelight valve control signals. Also a black out command may be sent to thelighting device (like that shown as 1050 of FIG. 10) from the remoteconsole 780 that is received by the communications node 730 and in turnis sent through conductors 729 to the microprocessor 728. The command isinterpreted by the microprocessor 728 and control signals are sent tothe motor drive device 722 to in turn operate the motors 846 r, 840 r,846 g, 840 g, 846 b, and 840 b. The motors 846 r, 840 r, 846 g, 840 g,846 b, and 840 b are operated to place a light blocking aperture fromthe aperture wheels 848 r, 844 r, 848 g, 844 g, 848 b, 844 b in front oflight before their respective light valves. When the light blockingapertures of the aperture devices are placed to block the light with alight blocking material in the light path from the color separators, theaperture devices are considered to be in the light blocking state.Aperture wheels 848 r and 844 r (with or without their motors 846 r and840 r) can be considered to be first and second components of a singleaperture device. Similarly aperture wheels 848 g and 844 g can beconsidered to be first and second components of a single aperturedevice. Similarly aperture wheels 848 b and 844 b can be considered tobe first and second components of a single aperture device.

[0100] It is also possible to reduce power to the lamp when themicroprocessor 728 of FIG. 7 determines that all three light valves 850r, 850 g, and 850 b are in the light blocking state. After themicroprocessor 728 determines this the microprocessor may next sendscontrol signals over the conductors 732 to control the lamp power supply724 to reduce the power to the lamp 810. By reducing power to the lamp810 the light output is reduced. When the light output is reduced byreducing power to the lamp 810 any light that is passing through thelight valves 850 g, 850 b, and 850 r in the light blocking state isreduced and thus improves the contrast ratio. If any of the three lightvalves 850 g, 850 b, or 850 r is determined by the processor 728 not tobe in the light blocking state a control signal is sent over theconductors 732 to control the lamp 810 power supply 724 to raise thepower to the lamp 810 for normal operation.

[0101]FIG. 10 shows two similar multiple light valve lighting devices1050 and 1060 connected over a communication system to a remote console780. The focussing lens 880 of the FIG. 8 embodiment is shown forprojecting an image onto a stage 1020. The stage could consist ofvarious projection materials including screens, drapes, walls andflooring as well as props and other materials known in the art of stagelighting. The components of the FIG. 8 embodiment are located in thelighting device 1050. The control system 760 of FIG. 7 is also locatedin the lighting device 1050.

[0102] The combined light path from the lens 880 to a stage orprojection surface 1020 a is shown as dashed lines 1054 and 1055. Device1060 is similar and may be identical to device 1050 and containsprojection lens 1062. A combined light path from the lens 1062 to thestage or projection surface 1020 a is shown by dashed lines 1064 and1065.

[0103] A remote console 780 sends commands over a communication systemas known in the art over the communication cables 772 and 778.Connectors 774, 1076 and 1084 connect the communication cables intointernal communication nodes (not shown) like 730 of FIG. 7. Connector770 connects the communication cable 772 to the remote console 780. Apower source 790 such as that provided by the power line is connected topower the console 780 at 796 and device 1050 at 794 and device 1060 at1095.

[0104] The lighting device like that shown as 1050 of FIG. 10 shouldhave a unique address so that it can respond to the command signals fromthe remote console 780 separately from other lighting devices such as1060 of FIG. 10 on the same communications system as known in the priorart. In FIG. 10, two lighting devices are shown however many more may beconnected to the same communications system. Some examples of commandsignals sent over the communication system from the remote console 780to the multiple light valve lighting device 1050 like that shown in FIG.10 are: lamp on, lamp off, black out, color modify red, color modifygreen, color modify blue, shutter open red, shutter close red, shutteropen green, shutter close green and shutter open blue, shutter closeblue, all shutters open, and all shutters closed.

[0105] The operator of the remote console 780 may command the lightingdevices 1050 or 1060 by using command signals over the communicationsystem to vary the color palette. This may be done at any time that thelighting devices 1050 or 1060 are in operation and can be used to createspecial effects and vary the visual look of the projected colors foraesthetic reasons. The operator inputs to the remote console 780 thedesired change to the color palette of a particular multiple light valvelighting device via a keypad or a switch entry system as known in theart. The remote console 780 processes the commands received by a keypad782 and transmits command signals over the communication system overcable conductors 772 and 1078. The command signals may also contain theunique address of the lighting device 1050 or 1060 that the operatorwishes to command. A multiple light valve lighting device such a device1050 of FIG. 10 receives the commands signals over the communicationssystem and next determines if the lighting device 1050 or 1060 has thecorrect unique address to respond to the command signals. If the uniqueaddress received matches the unique address of the lighting device 1050of FIG. 10, the lighting device 1050 next responds to the command signalby changing the color palette of the red, green or blue in accordancewith the command issued by the operator through the remote console.

[0106] There are several different types of light valves known in theart. There are digital mirror devices (DMD) made by Texas instrumentsand the Liquid Crystal Displays (LCD) made by various manufacturers. TheDMD is a reflective type light valve. LCD light valves may be of thereflective or transmissive type. FIG. 8 shows the transmissive type oflight valves. Systems built similarly to prior art FIG. 1 are also builtwith reflective light valves. Regardless of the use of a reflective ortransmissive light valves the aperture devices can be placed before orafter the light valves and after the color separator system to modifythe color before or after the light valves.

[0107] Although the invention has been described by reference toparticular illustrative embodiments thereof, many changes andmodifications of the invention may become apparent to those skilled inthe art without departing from the spirit and scope of the invention. Itis therefore intended to include within this patent all such changes andmodifications as may reasonably and properly be included within thescope of the present invention's contribution to the art.

I claim:
 1. An apparatus comprising a first light valve; a second lightvalve; a first color separator; a first aperture device; wherein thefirst color separator receives a first light comprised of a plurality offrequencies, and separates the first light into a first color light anda first residual light; wherein the first aperture device receives thefirst color light and the first aperture device can be controlled tomodify a frequency of the first color light; wherein the first lightvalve receives the first color light; and wherein the second light valvereceives at least a portion of the first residual light.
 2. Theapparatus of claim 1 wherein the first light is a white light.
 3. Theapparatus of claim 1 wherein the first light valve receives the firstcolor light after the first aperture device has modified the frequencyof the first color light.
 4. The apparatus of claim 1 wherein the firstlight valve receives the first color light before the first aperturedevice has modified the frequency of the first color light.
 5. Theapparatus of claim 4 wherein the first aperture device is comprised of afirst component and a second component.
 6. The apparatus of claim 5wherein the first component of the first aperture device is a firstaperture wheel; and the second component of the first aperture device isa second aperture wheel.
 7. The apparatus of claim 1 further comprisinga second aperture device; and wherein the second aperture devicereceives at least a portion of the first residual light and the secondaperture device can be controlled to transmit at least a portion of thefirst residual light to the second light valve.
 8. The apparatus ofclaim 7 further comprising a second color separator; and wherein thesecond color separator receives the first residual light from the firstcolor separator and the second color separator separates the firstresidual light into a second color light and a second residual light;and wherein the second aperture device receives the second color lightand the second aperture device can be controlled to modify a frequencyof the second color light to the second light valve.
 9. The apparatus ofclaim 1 wherein the first aperture device is comprised of a firstaperture wheel with a plurality of selectable apertures.
 10. Theapparatus of claim 9 wherein the first aperture device is comprised of asecond aperture wheel with a plurality of selectable apertures.
 11. Theapparatus of claim 9 wherein the first aperture wheel includes a lightblocking material in at least one of the plurality of selectableapertures.
 12. The apparatus of claim 1 wherein the first aperturedevice is comprised of a first component which includes a first filter.13. The apparatus of claim 12 wherein the first filter of the firstcomponent of the first aperture device is a cutoff filter.
 14. Theapparatus of claim 1 wherein the first aperture device is comprised of afirst component which includes a rectangular aperture.
 15. The apparatusof claim 1 wherein the first aperture device is comprised of a firstaperture wheel with a plurality of wedge shaped apertures.
 16. Theapparatus of claim 1 wherein the first aperture device is comprised of afirst component which includes a shutter.
 17. The apparatus of claim 1wherein the first aperture device is comprised of a first componentwhich includes a switchable spectral filter.
 18. The apparatus of claim1 further comprising a control system which receives a color modifyingcommand from a remote console; wherein the first aperture device iscomprised of a first component which is comprised of an aperture wheeland a motor; and wherein the control system in response to the colormodifying command sends a control signal to the motor and the motorresponds to the control signal by moving the aperture wheel.
 19. Theapparatus of claim 1 wherein a control system which receives a shuttercommand from a remote console; wherein the first aperture device iscomprised of a light blocking material; and wherein the control systemin response to the shutter command sends a control signal to the firstaperture device and the first aperture device responds by placing alight blocking material into the first color light path.
 20. Theapparatus of claim 1 further comprising a control system which iselectrically connected to the first light valve; and wherein the controlsystem automatically controls the first color light path of the firstcolor light, if the first light valve is determined by the controlsystem to be in a light blocking state.
 21. The apparatus of claim 1further comprising a control system which is electrically connected tothe first light valve; and wherein the first aperture device iscomprised of a first component which includes a light blocking materialand the first component of the first aperture device is controlled bythe control system to place the light blocking material of the firstcomponent into the first color light path of the first color light. 22.The apparatus of claim 1 further comprising a control system a remoteconsole; wherein a black out command from the remote console can bereceived by the control system which causes the control system tocontrol the first aperture device to block light from passing throughthe first aperture device.
 23. An apparatus comprising a first colorseparator for separating a first light comprised of a plurality offrequencies into a first color light having a first color light path anda first residual light; a second color separator for separating thefirst residual light into a second color light having a second colorlight path and a second residual light; a first aperture device locatedin a first color light path of the first color light; and a secondaperture device located in a second color light path of the second colorlight.
 24. The apparatus of claim 23 wherein the first light is a whitelight.
 25. The apparatus of claim 23 wherein the first aperture deviceis comprised of a first component which is driven by a motor; and thesecond aperture device is comprised of a first component which is drivenby a motor.
 26. A method comprising the steps of separating a firstlight comprised of a plurality of frequencies into a first color lightand a first residual light; supplying the first color light to a firstaperture device; controlling the first aperture device modify afrequency of the first color light to a first light valve; and supplyingat least a portion of the first residual light to a second light valve.27. An apparatus comprising: a first light valve; a second light valve;a first color separator; a first aperture device; wherein the firstcolor separator receives a first light comprised of a plurality offrequencies and separates the white light into a first color light and afirst residual light; wherein the first aperture device receives thefirst color light and the first aperture device can be controlled tosubstantially block the first color light to the first light valve; andwherein the second light valve receives at least a portion of the firstresidual light.
 28. The apparatus of claim 27 comprising a secondaperture device; a second color separator wherein the second colorseparator receives the first residual light from the first colorseparator and the second color separator separates the first residuallight into a second color light and a second residual light; and whereinthe second aperture device receives the second color light and thesecond aperture device can be controlled to substantially block thesecond color light to the second light valve.
 29. The apparatus of claim28 comprising a third light valve; and a third aperture device; whereinthe second residual light is comprised of a third color light; andwherein the third aperture device receives the third color light and thethird aperture device can be controlled to substantially block the thirdcolor light to the third light valve.
 30. The apparatus of claim 1further comprised of a lamp; and a third light valve; a microprocessorwhich is electrically connected to the first, second, and third lightvalves; wherein the lamp produces the first light and the lamp isconnected to a power supply and the microprocessor controls the supplyof power from the power supply to the lamp; and wherein themicroprocessor reduces power supplied from the power supply to the lampwhen the microprocessor determines that the first, second, and thirdlight valves are all in a light blocking state,
 31. The apparatus ofclaim 30 wherein If any of the first, second, and third light valves aredetermined by the microprocessor not to be in the light blocking statethe microprocessor increases power supplied from the power supply to thelamp.